Toyota 50-4FD100 Manual page 32

1-4
Engine mechanical (connecting rod and crank shaft)
Structure
Connecting rod
• The connecting rod is made of forged carbon steel. Its large end is horizontally split, which has
advantages in rigidity. The bush made of lead bronze with the oil groove in the center is pressed in its
small end.
• The connecting rod bolts are tightened by the plastic region tightening method.
Fitting direction of the bush joint
6
• As shown in the illustration, the plastic region tightening method is the way of tightening the bolts in the
plastic region where the change in the axial tension against the extension of the bolt is few. This method
has following characteristics.
Stable axial tension can be obtained: Because fluctuation in the axial tension is small comparing to elastic
region tightening, the axial tension can be stabilized.
High axial tension can be obtained.
There is a limit in reuse: Because plastic elongation is added at every time of it is reused, the frequency of
reuse is limited.
Refer to the J08E engine repair manual (
Match the bush oil hole with the con rod oil hole
Oil hole
Matching marks
Connecting rod (Looking at from the front of the engine)
) when reusing.